1. Field of the Invention
The invention relates to facilities on board ships for loading and unloading cargo, and in particular to a container ship of the type having one hull, a propulsion mechanism, and a handler that is movable along a guide disposed on a support.
2. Description of Related Art
At the present time there are three categories of container ships:
1) container ships that have no on-board handler, from which containers can only be unloaded in a port equipped with dock cranes,
2) container ships that have a container-handler such as cranes, traveling cranes, or portal cranes and that are able, entirely autonomously, to unload containers onto the dock of a port, and
3) container ships that have a handler that moves containers to a deck with which a ramp is associated, and from which a port transport device, such as a truck or rail car, unloads one or more containers via the ramp.
Ships in the third category are described in U.S. Pat. Nos. 4,158,416 and 3,591,023. These ships have either a movable bow or a movable stem, and thus need safety devices to ensure both closure and leak-tightness.
Ships in the second category are described in U.S. Pat. No. 4,043,285, which each have a hull and a framework that is integral with the hull. The framework includes vertical, lengthwise, and crosswise beams. The lengthwise beams have rails that support an overhead crane, and project beyond the stem of the hull. This projection, which is designed to overhang the dock of a port, enables the containers to be deposited directly onto the dock with the aid of the overhead crane.
Such an unloading device has the disadvantage of being only usable on large, high-tonnage ships on which movement of the container has little effect. However, this type of ship can only moor in deep-water ports, and the containers cannot be unloaded onto an unequipped beach, bank, or landing slip. Moreover, loading and unloading cannot be continuous where the rise and fall of the tide is substantial.
It is therefore an object of the invention to overcome these problems by providing a container ship that enables containers to be unloaded near a variety of points of use, i.e., not only in ports that are not equipped with port handling facilities but also onto unequipped beaches, banks, or landing slips. It is also an object of the invention to unload these containers, and to particularly place them on the ground. It is a further object of the invention to unload containers in such a manner that it has practically no effect on the equilibrium of the ship, whatever its size.
These objects are achieved by providing a container ship of the type having a hull, a propulsion mechanism, and a handler that moves along a guide disposed on a support, wherein the guide is extendible beyond the hull of the ship.
In accordance with one aspect of the invention, the support includes at least one beam attached to the hull, that supports a first part of the guide of the handler, and that has a lengthwise cavity, inside of which is disposed a second, movable beam that supports a second part of the guide. The second part of the guide constitutes an extension of the first part when the movable beam is deployed beyond the ship""s hull.
In accordance with another aspect of the invention, the support includes at least two beams attached to the hull inside which are disposed one movable beam, at least one cross beam, or a plate connecting the at least two movable beams.